HISTORICAL VIGNETTE J Neurosurg 130:1006–1020, 2019 The history of therapeutic hypothermia and its use in neurosurgery Michael A. Bohl, MD,1 Nikolay L. Martirosyan, MD, PhD,1 Zachary W. Killeen, MD,2 Evgenii Belykh, MD,1,3 Joseph M. Zabramski, MD,1 Robert F. Spetzler, MD,1 and Mark C. Preul, MD1 1Department of Neurosurgery, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, Arizona; 2University of Arizona College of Medicine, Phoenix, Arizona; and 3Irkutsk State Medical University, Irkutsk, Russia Despite an overwhelming history demonstrating the potential of hypothermia to rescue and preserve the brain and spinal cord after injury or disease, clinical trials from the last 50 years have failed to show a convincing benefit. This compre- hensive review provides the historical context needed to consider the current status of clinical hypothermia research and a view toward the future direction for this field. For millennia, accounts of hypothermic patients surviving typically fatal circumstances have piqued the interest of physicians and prompted many of the early investigations into hypother- mic physiology. In 1650, for example, a 22-year-old woman in Oxford suffered a 30-minute execution by hanging on a notably cold and wet day but was found breathing hours later when her casket was opened in a medical school dis- section laboratory. News of her complete recovery inspired pioneers such as John Hunter to perform the first complete and methodical experiments on life in a hypothermic state. Hunter’s work helped spark a scientific revolution in Europe that saw the overthrow of the centuries-old dogma that volitional movement was created by hydraulic nerves filling muscle bladders with cerebrospinal fluid and replaced this theory with animal electricity. Central to this paradigm shift was Giovanni Aldini, whose public attempts to reanimate the hypothermic bodies of executed criminals not only inspired tremendous scientific debate but also inspired a young Mary Shelley to write her novel Frankenstein. Dr. Temple Fay introduced hypothermia to modern medicine with his human trials on systemic and focal cooling. His work was derailed after Nazi physicians in Dachau used his results to justify their infamous experiments on prisoners of war. The latter half of the 20th century saw the introduction of hypothermic cerebrovascular arrest in neurosurgical operating rooms. The ebb and flow of neurosurgical interest in hypothermia that has since persisted reflect our continuing struggle to achieve the neuroprotective benefits of cooling while minimizing the systemic side effects. https://thejns.org/doi/abs/10.3171/2017.10.JNS171282 KEYWORDS cold water submersion; history of neurosurgery; hypothermia; therapeutic cooling OR millennia, physicians have recognized the thera- and detrimental effects of hypothermia on human physiol- peutic effect of hypothermia on patients suffering ogy and pathophysiology grew, so did our willingness to neurological illness or trauma. Indeed, these at- induce hypothermia in hopes of achieving better patient Ftempts to preserve or rescue neural tissue are ultimately outcomes. Hypothermia was thus introduced into modern designed to preserve function. In more modern times, neurosurgery in the early 20th century, with promising neurosurgeons have attempted to use surgery or special- early results. The Second World War posed a significant ized treatments to influence complex brain or spinal cord setback for hypothermia research, in large part due to functions. History has shown this journey to be filled with negative associations with Nazi experiments. However, by tremendous promise and enormous pain. the 1950s, cardiac surgeons and neurosurgeons had again Accounts of hypothermic patients seemingly miracu- begun experimenting with the effects of whole-body and lously recovering from typically fatal circumstances have local cooling. Recognition of the comorbidities conferred piqued the interest of scientist-physicians for centuries, by moderate hypothermia led to a decline in interest prompting many of them to carry out the early animal through the 1970s, but interest re-emerged in the 1980s as and human investigations that laid the foundation of our a result of studies showing better risk-benefit profiles with modern understanding of how cooling affects the central mild rather than moderate hypothermia. The publication nervous system. As our understanding of the beneficial of clinical trials showing a benefit of induced hypothermia ABBREVIATIONS BRL = Brain Research Laboratory; SCI = spinal cord injury; TBI = traumatic brain injury. SUBMITTED June 8, 2017. ACCEPTED October 20, 2017. INCLUDE WHEN CITING Published online May 25, 2018; DOI: 10.3171/2017.10.JNS171282. 1006 J Neurosurg Volume 130 • March 2019 ©AANS 2019, except where prohibited by US copyright law Unauthenticated | Downloaded 10/06/21 08:23 PM UTC M. A. Bohl et al. following out-of-hospital cardiac arrest led to a perma- nent place for hypothermia in the resuscitation literature. In contrast, the neurosurgical literature has remained far more ambiguous regarding the utility of hypothermia as a neuroprotectant. Pre–Modern History of Hypothermia in Neurosurgery Antiquity The Ancient Egyptians Among the most legendary ancient Egyptian physicians was Imhotep (c. 2780 BCE), chief advisor to the pharaoh Zoser and regarded historically as an expert physician, surgeon, astrologer, architect, engineer, and priest. His accomplishments gained him the authority to design and oversee the building of the step pyramids at Saqqara, a position that many believe he used to systematically study the various injuries incurred by the slaves tasked with lift- ing the great stones used to construct the pyramids. Al- though Imhotep was never known to have recorded the results of his investigations, evidence exists to suggest that his medical teachings and wisdom were passed down for centuries and eventually recorded on the famous Edwin Smith papyrus.12,13,21,23,37,57,76,79 The Edwin Smith papyrus is significant for many rea- sons. As the oldest medical text yet discovered, it details the origins not only of neurosurgical procedures, but also of plastic, orthopedic, and oral-maxillofacial procedures. More interesting, however, is how it was written as an ob- jective, systematic guide to patient care with a focus al- most entirely on physical treatments of disease rather than magical cures or protective prayers. The text reads as a 48-patient case series of injuries and other maladies com- monly encountered at that time, organized from head to toe and from less to more severe. Each case begins with a title, and in each title is a hieroglyph meaning “knowl- edge gained from practical experience.” Each case is FIG. 1. Engraving of Hippocrates (c. 460–c. 370 BCE) on the frontispiece furthermore organized into history, physical, diagnosis, of his famous work translated by Francis Clifton, “Upon Air, Water and prognosis, and treatment—the earliest recorded evidence Situation: Upon Epidemical Diseases: and upon Prognosticks, in Acute of our modern-day approach to patient care. At the end Cases Especially,” London, 1734. Image engraved by G. Van der Gucht of each case comes 1 of 3 treatment suggestions based on from a drawing by Peter Paul Rubens of a bust of Hippocrates; the prognosis: “an ailment I will handle,” “an ailment I will engraved image is a rendering of Hippocrates according to the artists’ fight with,” or “an ailment for which nothing is done.” imaginations. Figure is in the public domain. The papyrus is significant to the field of hypothermia as it contains the earliest historical evidence of our using the ing to see which areas of the body dried first. The theory effects of cold to treat disease. Case 46, specifically, is a was that the mud would dry fastest in those areas with practical guide to the treatment of a noninfectious chest excess heat, and where there was excess heat, there was blister, “an ailment I will handle.” The recommended disease. In keeping with this theory, Hippocrates or as- treatment is application of cool media. Considering the sociated philosopher-physicians became the first to induce difficulty that ancient Egyptians likely had in discovering hypothermia in patients as a form of treatment, specifi- ways to keep things cool, the author included instructions cally in patients suffering from tetanus, although these on preparing this cool media: “Fruit, natron, and mineral, ideas changed over time. However, Hippocrates suggested ground and bandaged on it; or calcite powder, mineral, that cold may have acute, regional effects as well: “cold builders mortar, and water, ground and bandaged on it.”13 should be applied in the following cases: when there is hemorrhage or the danger of one. In such cases apply the Hippocrates cold not to the actual spot from which the bleeding occurs More than 1000 years later, the Hippocratic school or is expected, but round about.… Swelling and pain in of medicine was established in ancient Greece (Fig. 1). the joints unassociated with ulceration, gout and spasms, One of its particularly innovative diagnostic techniques are mostly relieved and reduced by cold douches and the was the covering of patients in wet mud and then watch- pain thus dispelled. A moderate numbness relieves pain.”43 J Neurosurg Volume 130 • March 2019 1007 Unauthenticated | Downloaded 10/06/21 08:23 PM UTC M. A. Bohl et al. FIG. 2. Left: A woodcut from c. 1651 depicting the hanging of Anne Greene. A militiaman is depicted beating on her chest with the stock of his musket, and relatives pull on her feet in hopes of ending her misery more quickly. The upper left corner of the image depicts her resuscitation and rewarming. Right: William Petty (May 26, 1623–December 16, 1687) at the time of his election as professor of anatomy at Oxford. (Portrait by Isaac Fuller c. 1651.) Left panel: public domain. Right panel: © National Portrait Gal- lery, London. Used with permission. Although theories at the time that cold and its effects on retribution and eventually gave birth to a premature still- the human body were incomplete or unassociated obser- born baby that she attempted to hide.